Interpretive Summary: Adult females of the honey bee mite, Varroa destructor, have fungi on their surfaces, and spread the fungi throughout the bee colony. Fungi present are typical of those associated with bees, their combs and provisions, and are common filamentous, soil saprophytes (listed in order of relative abundance): Penicillium, Aspergillus, Fusarium, Trichoderma, Alternaria, Rhizopus and Mucor. These fungi have no biological control implications (i.e. entomogenous) because none were recovered internally within the mites; absence of fungi internally also reveals that this mite is not a fungivore. One of these, Aspergillus flavus, a new record for the honey bee mite, is uniquely pathogenic to honey bees (stonebrood disease), and implicates varroa as an important fungal vector.

Technical Abstract:
An isolation procedure, modified from plant pathology that permits recovery of internal fungi was adapted for use on varroa to determine whether they harbor internal fungi. The external mycoflora of the mite was also examined to explore what types of fungi these mites may disperse within the bee colony. The consistency and diversity of the mycoflora were also investigated among three different mite populations, representing Arizona, Florida and Maine.